Folios of the type described above comprise at least one main body portion dimensioned to be slightly larger than the standard size, and at least one pocket of cardboard, plastic foil or another flat material rigidly connected, on at least two sides thereof, to the main body portion. A folio or case of this type is disclosed in German utility model 89 05 631, wherein pocket flaps are joined to the opposite narrow sides of the rectangular body through folding edges, i.e., fold lines at the adjoining edges. The pocket flaps are affixed at the lateral edges thereof to the longitudinal sides of the main body. Provided on the lateral edges of the pocket flaps to be secured to the main body, or of the main basic body (or of both), are filing tongues or tabs protruding outwardly from the lateral edges and having no folding edge. If these tongues are folded inwardly, they tend to gape or bridge open a folio in the collapsed condition. The filing tongues of such conventional folios or cases are admittedly useful because they permit, as opposed to other state-of-the-art folders or cases, filing operations within a folder. However, these filing tongues interfere with or detract from the imposing character of presentation folios or cases, and cause inconvenience during handling.
In respect of folios having two main bodies in adjoining relationship through back folding edges with no pockets, German utility model 74 20 788 and Austrian patent 280944 disclose cutting a filing tongue including filing perforations from a main body. This filing tongue is capable of being unfolded beyond the back, exposing a filing mechanism (if provided in the folio), and thereby spoiling the imposing character of the case. However, what is more aggravating is the disadvantage that the filing tongues at the ends of the folding edges easily break, thereby destroying the utility of the folio. The risk of breakage is particularly likely if, according to German utility model 74 20 788, the folding edge of the filing tongue is disposed at a distance from the back of the folio because, in such a case, the center of gravity of the folio is located laterally of the filing tongue. Folios of this type must therefore in practice be made of a tear-resistant plastic material and thus the cost is correspondingly high; nevertheless they are suitable for representative purposes to a limited extent only.